Title: Electrophysiological assessment of auditory transmission by Brainstem Evoked Response Audiometry in subclinical hypothyroidism without any clinical hearing loss
Authors: Dr Subhradev Biswas, Dr Piyali Das, Dr Ankit Choudhary
DOI: https://dx.doi.org/10.18535/jmscr/v7i4.174
Abstract
Although overt hypothyroidism is often found be associated with delayed neuronal transmission, subclinical hypothyroidism is not adequately explored in this regard specially in our geographic area. In the present study attempt was made to check whether auditory transmission gets impaired in subclinical hypothyroidism even in absence of clinical deafness. We assessed adequacy of hearing transmission in 30 subclinical hypothyroid candidates without any clinical hearing loss and 30 age, gender matched healthy euthyroid control by Brainstem Evoked Response Audiometry. We found significant prolongation of absolute latencies of wave I and V and inter peak latencies of I-V, III-V and significant reduction of wave V amplitude in subclinical hypothyroidism. We also found significant negative correlation offree T4 (fT4) with absolute latencies of wave I and V and positive correlation with Wave V amplitude. Study also revealed significant negative correlation of serum TSH with absolute latency of wave I and interpeak latency of III-V. Therefore, present study concludes that, auditory transmission may get impaired in subclinical hypothyroidism even in absence of clinical deafness that can be authentically assessed by Brainstem Evoked Response Audiometry. Severity of hypothyroid state may have positive correlation with impairment of auditory transmission.
Keywords: subclinical hypothyroidism, deafness, Brainstem Evoked Response Audiometry.
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